Combined starter and generator



April 10, 1962 R. c. NODDIN 3, ,3

COMBINED STARTER AND GENERATOR Filed Aug. 18. 1958 2 Sheets-Sheet 1-EEGLJLATIFIG; FIELD FOE GENERATOR and SHUNT F'lEL'D FOR STARTER.

(VOLTAGE cou n4 cu'rou-r REA-A7) o l A v CUTOUT "RELAY (UNENE'JZGIZEDPos.)

STAETEE swrrcH @RTER' SOLENOID ill I} MAIN SHUNT FIELD I i 1 5 1! GIINVENTOR. EAV C. NODDIN ATTOP/VE Y April 10, 1962 R. c. NODDIN 2 ,3

COMBINED STARTER AND GENERATOR Filed Aug. 18, 1958 2 Sheets-Sheet 2(VOLTAGE. Cau. m

'EEGULATING FIELD FOE C-UTOUT Y) GENERATOR and SHUNT FIELD F012STA'ETE'Z.

C I'ECUIT BREAKER i STARTER SOLENOID MAIN SHUNT FIELD INVENTOR. RAY CL.NODDIN ATTOP/VEY.

United States Patent 3,029,350 COMBINED STARTER AND GENERATOR Ray C.Noddin, Chicopee, Mass, assignor to American Bosch Anna Corporation, acorporation of New York Filed Aug. 18, 1958, Ser. No. 755,521 2 Claims.(Cl. 290-31) This invention relates to a new and improvedstartergenerator system and has particular reference to the provision ofsuch a system for use in accordance with small gasoline operated motors.

The principal object of the invention is to provide a new and improvedstarter-generator system for use in connection with small gasolinemotors.

Another object is to provide a device of the type set forth which deviceincludes means for utilizing the selfregulating field of the generatoras a full shunt field during the starting of the electric motor whichsaid device accompanies.

Another object is to provide an arrangement of the type set forth whichdevice produces a higher starting torque than standardstarter-generators.

Another object is to provide an arrangement of the type set forth whicharrangement includes a flatter generator regulation characteristic thanstandard starter-generators.

Another object is to provide an arrangement of the type set forth whicharrangement provides a less expensive winding in the many applicationsin which use of the series field is unnecessary.

Another object is to provide an arrangement of the type set forth thatis less expensive and simpler to operate than standardstarter-generators.

Another object is to provide an arrangement of the type set forth thatutilizes the self-regulating field as a full field shunt duringstarting.

Other objects and advantages of the invention will be apparent from thefollowing description taken in connection with the accompanyingdrawings. It will be understood that changes may be made in the detailsof construction and arrangement of parts shown and described as thepreferred forms have been given by way of illustration only.

Referring to the drawings:

FIG. 1 is a schematic presentation of the starter-generator without theinclusion of a circuit breaker; and

FIG. 2 is a schematic presentation of the starter-generator with theinclusion of the circuit breaker.

Referring more particularly to the drawings wherein correspondingreference characters designate similar parts throughout, the arrangementshown in FIG. 1 comprises an armature connected through a suitable leadto a ground G a main shunt field coil circuit connected across saidarmature, and a cutout relay or energized position connected through asuitable lead from the top of said armature.

The arrangement further includes a regulating field for the generator(or shunt field for the starter as it some times operates) connectedthrough suitable leads to said cutout relay; said cutout relay beingfurther connected through suitable leads to resistor R and thence toground G Said regulating field for the generator is further connected tothe battery b which the system is regulating and thence to ground 6;,through suitable leads.

The arrangement also comprises a starter solenoid connected throughsuitable leads to the rest of the system including ground G thus,completing the starter generator system.

The windings of said system are essentially the same as those ofstandardstarter-generators with the aforementioned optional use of theseries field.

The arrangement shown in FIG. 2 comprises the same r 3,029,350 PatentedApr. 10, 1962 ice arrangement of component parts as the arrangement inFIG. 1 with the exception that said arrangement inFIG. 2 comprises acircuit breaker in addition to those components shown in FIG. 1.

Said circuit breaker is located immediately above the main shunt fieldof the starter-generator system and operates only when the ambienttemperature rises to a predetermined limit.

In the drawings, R is the voltage coil in the cutout relay. D is thereverse current coil in the cutout relay and X is the switch forenergizing starter solenoid coil and winding A.

In operation, the arrangement shown in FIG. 1 operates similarly toexisting start-generator systems with the exception that theself-regulating field of the generator operates so as to be both aregulating field for the generator and a shunt field for the starter.

The field winding C is the main exciting winding used in generation.

The switch X is closed and this energizes starter solenoid coil andwinding A. Starter solenoid coil A closes the starter switch to providevoltage to armature B. Winding A, when energized, provides a very strongshunt field during starting and during this period the cutout relay isopen.

When the engine starts, switch X is opened, opening the starter switchand removing winding A circuit from ground G As the engine speed hasbuilt up the voltage, the generated armature B voltage builds up becauseof self excitation in field C. At a predetermined level, the current incoil R will close the cutout relay thereby connecting the output ofarmature B to the battery through field A.

In operation, the arrangement shown in FIG. 2 operates similarly to thearrangement shown in FIG. 1 with the'exception that the arrangement inFIG. 2 includes a circuit breaker which operates, in fact, as a currentregulator. Said circuit breaker is closed during both the starting ofthe engine and the initial stages of generation; thus, permitting arapid initial recharge of the battery.

During this condition of rapid charge and heavy shunt field current, thegenerator heat rises relatively rapidly until the predetermined safethermal limit is reached, at which said circuit breaker opens. Then boththe shunt field current and charging current drop, thereby, protectingthe generator thermally and protecting the battery from overcharge.

This condition prevails until the generator is stopped or until saidcircuit breaker recloses beginning the cycle again. Excess reversecurrent during operation at idle speed with said circuit breaker open isprevented by a high setting voltage-wise on the cutout relay.

Thus, subject to these two innovations, the startergenerator operates asdo existing ones.

From the foregoing, it will be seen that I have provided simple,efiicient and economical means for obtaining all of the objects andadvantages of the invention.

I claim:

1. In a combined starter and generator for internal combustion engines,an armature, a main shunt field coil circuit connected across saidarmature, a second com bined regulating and shunt field coil circuit anda switch and circuit connections constructed and arranged forselectively connecting said second field coil circuit to be selectivelyconnected to said armature or said starter and to be used as a shuntfield in starting and as a difierential series field in generating.

2. In a combined starter and generator for internal combustion engines,an armature, a main shunt field coil circuit connected across saidarmature, a second combined regulating and shunt field coil circuit anda switch and circuit connections constructed and arranged for 3*se'leetiv'sry connectin said secbud field coi-l circuit to be'"selectivelywnnnected tvsid armature'or said starterand to be used as ashunt field in starting and as a differential series field ingenerating, and a circuit breaker across said fes'istor in the mainshunt field circuit and constructed andafrang'edto be opened byheat-resulting from operation 'o'f'the generator for'lowering the geneiatoroutput to prevent overcharge of the battery and overheating of'the*generator.

References Cited in the file of this patent Beetern July 12, 1932Turbayne Sept. 18, 1923 Watson May 10, 1927 Perk-ins "he." Feb. 26, 1929

